Manufactured Runs

How Often Do Deadline Deals Pay Off?

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As the non-waiver trade deadline approaches, there’s been a flurry of activity. But how much of a difference do these deadline deals really make? Can a key acquisition make the difference between playing in October and staying home?

We can measure this by looking at a stat called Wins Above Replacement Player, which measures how well a player performs compared to a hypothetical backup. When evaluating in-season moves, this is a good, but not perfect, proxy for a team’s available assets. It’s a composite of the options available to a typical team, which can ignore some finer points of roster management. Most teams, after all, make deadline deals to shore up weaknesses, not strengths. So comparison to backups, rather than an average player, is a better model for the reality most GMs face.

Looking at deadline deals since the introduction of the Wild Card in 1995, we see a bevy of moves. By rough count, looking at the past-season WARP of the players acquired versus the players given away, we can see that 180 of those deals were ones where a team was buying talent (as opposed to selling or moves where little talent was moving in either direction). But how many of those deals had a significant impact on the division race? Reviewing the record, there are just 10 teams that made “impact” deals.

Probably the greatest acquisition in terms of sheer value on the field was the Brewers’ acquisition of C.C. Sabathia in 2008. Sabathia provided the Brewers with 4.2 WARP down the stretch , roughly twice what an average full-time position player can produce in a full season. Sabathia did this by being both good and a workhorse, pitching an incredible 17 games and seven complete games for the Brewers in less than half a season. Given the Brewers won the wild card by a single game, that was definitely the difference between playoff success and an October spent at home.

Oddly enough the second-best deadline deal WARP came the same year, when the Dodgers acquired Manny Ramirez in a three-team deal. The Dodgers won their division by a scant two games, and Manny responded to the deal by slugging an incredible .743 down the stretch with 17 home runs. That same deal might have cost the Red Sox their division, as well—Manny produced 4.0 WARP for the Dodgers, compared to the 1.4 WARPJason Bay produced as his replacement in Boston. The Red Sox finished two games back of the Rays, who would defeat the Red Sox later on in the ALCS. Of course, you can’t just assume that all things would have been equal had the trade not been made—the Red Sox had come to question Ramirez’s commitment, and there is no way of knowing what he would have produced had he remained in Beantown.

Not all trades have to be blockbusters to make a difference, and it may not be any one deal that pushes a team over the top. The 2007 Phillies picked up three players—Tadahito Iguchi, Kyle Lohse, and Julio Mateo—in three separate deals. Those players combined to give the Phillies 1.4 WARP over what they dealt away, and the Phillies made the playoffs that year by a single game.

So, deadline deals can make a big impact on a team’s chances of reaching the playoffs, but it’s important to remember that they typically don’t. Finding one or two players who can combine for a significant value is difficult, and getting those players to have a hot streak on cue is harder still. Most teams get into a position to acquire talent at the deadline by having a roster stocked with talented baseball players, and how those players perform down the stretch is generally far more important than the work of one or two players brought in to bolster a squad.

Certainly interesting though not very surprising. Quick back-of-envelope math shows the NL West champion--by a pretty good margin--winning their division by the smallest margin of the six since the last strike, so it makes sense that they represent 1/3 of the pack.

Since the 3rd place team in the AL East has finished 14+ games behind the 1st place team in that division on average the last 16 years, and the runner-up between them tends to be the wild card team more than their 'fair share' it's no surprise not to see a AL East team listed. I'd guess a lot of deadline deals in that division tend to be similar to the build-for-later move we saw Anthopoulos make on Wednesday.

I was a bit surprised that the Central divisions were not more heavily represented, since those always come to mind as the fairly level but blah divisions that a handful of teams can win in a given year.

The Phillies won the NL East in 2008 by three games but Tadahito Iguchi, Kyle Lohse, and Julio Mateo still got credit for their 1.4 WARP on this list as an impact deal. I imagine that pitching Oswalt instead of Kendrick also helped the bullpen's performance by affording them some extra rest.

Remember, sometimes it's not just the value of the player acquired, it's his improvement over the alternative. These numbers are fine if the prior placeholder was 0 WARP, but in some cases, a player has contributed more by replacing a Yawning Vortex of Suck.

To take this a step further, can deadline deal acquisitions be shown to have a positive impact on the WARP/G of their new teammates?

Finally, some deals are made not to get the team into the postseason, but as insurance to make sure they do, and for what they are hoped to contribute once they get there. Not sure how to put a value on that.

I don't doubt that there's some "wiggle room" and some things not quantified here - like I said, I think WARP is a useful proxy for the kinds of roster decisions that GMs have to make in these circumstances, but the reality is much more complicated.

I still think this not only tells us something about deadline deals, but helps us put a face on it - I can step you through some really dry math that tells a very similar story. What it turns out is that a typical everyday ballplayer can only be expected to give you roughly two marginal wins (in this case the margin is replacement level) a season. At this point, roughly two thirds of the season is over, so you get roughly a third of that, or about .67 WARP. Now that's the average - sometimes you get more, but sometimes you get less.

And of course a lot of deadline deals aren't for full-time starters at all. They're for an extra bench bat or some extra middle-relief arms.

So I think you could redo this analysis with some tweaks here and there - some of the dividing points are admittedly a little capricious. But I don't think you'd come up with a substantially different answer.

(And if you want to know about how a particular deadline deal affected a particular team, you'd probably want to look at the ACTUAL replacements, rather than the theoretical replacement level used in WARP.)